The Little Mermaid

In the original version, the Little Mermaid feels an indescribable amount of pain every time she takes a step - due to a curse the witch put on her.
The Little Mermaid has a mother in the original - her mother is dead in the Дисней version.
The Captain that the mermaid falls in Любовь with marries another woman (whom he had been in Любовь with in the first place) - in the Дисней version the Little Mermaid gets the prince!
The Little Mermaid's sisters offer her a нож to kill the prince so she can return to the see in the original.
The Little Mermaid dies at the end (turns into sea foam) - she kinds of commits suicide - because she cannot bare to see the prince with someone else.

Snow White

In the original - the Queen requests the lungs and liver (as well as the heart) of Snow White to eat for ужин that night.
In the original - Snow White is not awakened by a Kiss from the prince (like the Дисней version) - she is awakened when she is jostled by the horse on which her coffin is being carried by the prince.

Cinderella

In the original - the step-sisters of Золушка try to cut off different parts of their feet to make them fit into the glass slippers.
The Prince is alerted of the step-sisters by two carrier pigeons who then peck out the step-sisters eyes. The step-sisters live as blind beggars for the rest of their lives.

Sleeping Beauty

Woman is put to sleep because of a prophecy (not a curse) in the original.
In the real original (not Brothers Grimm version) - Sleeping Beauty is raped by the King (her father) and is awakened when her child sucks the piece of лен, лён that was keeping her asleep out of her finger.